As video technology advances, so do the possibilities of health issues for young children. The new 3-D video games use a visual trickery that can lead to headaches, motion sickness and possibly impaired vision.

Nintendo, the game maker, acknowledged the concerns last week when it issued an unusual caution, even before its long-awaited 3DS hand-held game machine debuts in U.S. stores as soon as March.Nintendo says children 6 years old and younger should not use the device because of the risk of lasting damage to ocular development.

No one really knows what the risk is, however, because there's scant research on how the latest wave of 3-D technology affects young eyes. Nintendo touts its 3DS system as revolutionary: No dorky glasses required. The breakthrough is made possible by tiny prisms embedded in high-resolution screens that scatter digital images into stereo visual 3-D.

Even though your child might be begging for a 3-D game, parents should research this issue and keep tabs on all further developments.